New predictions of animal population doom are likely exaggerated.

Stanford biologist Paul Ehrlich has made a gaudy career of prophesying imminent ecological doom. "In the 1970s hundreds of millions of people will starve to death in spite of any crash programs embarked upon now," he declared in his 1968 manifesto The Population Bomb. In the subsequent 50 years, as world population more than doubled, the proportion of chronically undernourished people in the world dropped from 33 percent in 1968 to 11 percent now.

Ehrlich is now predicting population doom for the world's animals. The cause? Human overpopulation, naturally. Ehrlich and his colleagues Gerardo Ceballos and Rodolfo Dirzo describe the allegedly impending "biological annihilation" of about a third of all vertebrate land species in a paper for The Proceedings of the National Academy of Sciences.

"The ultimate drivers of those immediate causes of biotic destruction [are] human overpopulation and continued population growth, and overconsumption, especially by the rich," they argue. "All signs point to ever more powerful assaults on biodiversity in the next two decades, painting a dismal picture of the future of life, including human life." The crisis supposedly results from "the fiction that perpetual growth can occur on a finite planet"; meanwhile, "the window for effective action is very short, probably two or three decades at most."

Ehrlich and his colleagues reached those conclusions by taking the International Union for the Conservation of Nature's data on populations of 27,600 species of mammals, birds, reptiles, and amphibians and overlaying those figures on a grid of 22,000 plots measuring 10,000 square kilometers across all of the continents. The goal is to identify areas where local populations of each species has been extirpated. They report that since 1900 "nearly half of known vertebrate species, 32% (8,851/27,600) are decreasing; that is, they have decreased in population size and range."

This not the first time the alarms of mass extinction has been raised. In 1970, Dr. S. Dillon Ripley, secretary of the Smithsonian Institution, predicted that between 75 and 80 percent of all species of animals would be extinct by 1995. In 1979, the Oxford biologist Norman Myers suggested that the world could "lose one-quarter of all species by the year 2000." Also in 1979, the Heinz Center biologist Thomas Lovejoy chimed in, estimating that between a seventh and a fifth of global diversity would become extinct by 2000. None of those dire predictions came true.

Ehrlich and his dour colleagues are probably wrong too, thanks to human ingenuity and the very trends in "perpetual growth" that they think are threats to biodiversity.

First, human population will peak this century at perhaps as few as 8.2 billion people. The United Nations projects that 80 percent of those will be living in cities by 2100, meaning that fewer than 1.6 billion people will be living on the landscape, down from 3.2 billion now. Humanity may already be at peak farmland. If biofuel subsidies are stopped, some researchers project that as much as 400 million hectares of land would be returned to nature by 2060; that is an area double the size of the United States east of the Mississippi River.

Many countries have now gone through the forest transition and their forests are expanding. More broadly, the global rate of deforestation has been declining. Furthermore, there is evidence that "dematerialization": Thanks to technological progress, humanity is using relatively less stuff to obtain more services. Current trends suggest that humanity is likely to withdraw increasingly from nature over the course of this century, thus relinquishing a great deal of territory in which our fellow creatures will be able to thrive.

In fact, a very different and much more positive story can be told about how biodiversity is faring around the world. In a forthcoming book, Inheritors of the Earth: How Nature Is Thriving in an Age of Extinction, University of York conservation biologist Chris Thomas points out that at reasonable scales—say, regions the size of Vermont—humanity has actually been enriching local biodiversity. How? By moving around and introducing species to areas they were previously absent. New Zealand's 2,000 native plant species have been joined by 2,000 from elsewhere, doubling the plant biodiversity of its islands. Meanwhile, only three species of native plants have gone extinct.

In many cases, as I reported in my book The End of Doom, the newcomers may actually benefit the natives. In a 2010 review article in the Annual Review of Ecology, Evolution, andSystematics, the Rutgers ecologist Joan Ehrenfeld reports that rapidly accumulating evidence from many introduced species of plants and animals shows that they improve ecosystem functioning by increasing local biomass and speeding up the recycling of nutrients and energy. Similarly, as a 2012 review article in Trends in Ecology and Evolution notes, "ecological theory does not automatically imply that a global decline in species richness will result in impaired functioning of the world's ecosystems." In other words, the foundations of civilization are likely not imperiled even in the dubious event that Ehrlich's mass extinction occurs.

I mourn the loss of species. Each species embodies complex genetic libraries, behavioral repertoires, and evolutionary histories that are both scientifically fascinating and aesthetically fulfilling. As a relatively well-off First Worlder, I have had the intense pleasure of walking in the wild within 40 feet of grazing rhinos and of swimming with Galápagos penguins. It would be a shame if future generations do not have an opportunity to enjoy such experiences.

Fortunately, Ehrlich's new extinction predictions are likely to be as accurate as his famine forecasts.

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Yup, that I why I think we can have nice things and animals we know and love.

I was thinking about how the government sought to eradicate the Buffalo (American Bison) and the herd got down to possibly 541 animals. A handful of ranchers collected the remaining Bison and began to bred the herd to higher levels.

I’ve seen these “sixth extinction event” scares recently and figure the primary reason they are full of shit is that the fossil record tracks so few species. Look at just the zillions of species with bones or shells which would actually show up as fossils in 100M years, or even 1M years — consider how subtle the differences are among similar species, whether all living now or separated by just a few thousand years.

Then compare that to how many species show up in fossils. The dinosaurs alone cover 100M years or so, yet there are only a few hundred known dinosaur species.

These dummies think that just because we lose, what, 100, 100, 10000 species a year, that is so huge compared to known dinosaur species, that we are DOOMED, DOOMED. But it ain’t even a drop in the bucket compared to how many unknown dinosaur species were created and destroyed every year and never made it into museums.

Ron, thank you for this. I am still doubtful that things are as rosy as you say, but at least you provide actual evidence addressing Ehrlich’s points and you acknowledge that we shouldn’t kill off species.

They report that since 1900 “nearly half of known vertebrate species, 32% (8,851/27,600) are decreasing

I wouldn’t describe 32% as “nearly half.” “Nearly one-third” would be more accurate, but of course that doesn’t have the same fear inducing effect as saying ‘OMGZ, nearly half of known verterbrate species are going to go extinct because EVUL humanz! Especially those dastardly rich peepul!”

I freely admit that I like to tease Ron Bailey as much as possible, but after reading that quote, I just feel to sorry for him; having to read and critique stuff like that in the course of trying to do your job constitutes cruel and unusual punishment. Reading Paul Ehrlich is just plain torture.

Ehrlich and his colleagues reached those conclusions by taking the International Union for the Conservation of Nature’s data on populations of 27,600 species of mammals, birds, reptiles, and amphibians and overlaying those figures on a grid of 22,000 plots measuring 10,000 square kilometers across all of the continents. The goal is to identify areas where local populations of each species has been extirpated. They report that since 1900 “nearly half of known vertebrate species, 32% (8,851/27,600) are decreasing; that is, they have decreased in population size and range.”

I am confident that the population distribution of animals in Africa, Asia, and South America was very precisely known in 1900, so this study is totally valid.

A few years back I took a vacation to Hawaii and of course on the islands ‘invasive species’ are considered a big deal.

The way its discussed is basically to say that if you introduce any non-native species to an area, the non-native species will quickly result in the elimination of native species and the non-native becomes dominant.

Then I realized something. There were quite likely hundreds of species artificially introduced to the Hawaiian islands. Most of them couldn’t actually compete with the native species and they died out quickly. Only a bare handful could actually hack it.

Hog hunting with a bunch of big dogs and a knife was a hobby of our guide on a bike ride around Kilauea.

Looking at the bag limits and restrictions on hunting them, it doesn’t seem like they really want to attempt to eradicate or seriously reduce the population of them. Wonder if thats a thing of outfitters having a bit of undo influence.

“How many of these ‘native species’ were once ‘invasive species’ introduced to the islands by the first Polynesian settlers?” Of course, those species were introduced by indigenous (IOW brown-skinned) people, not us EVUL pale skinned European bastards.

“The way its discussed is basically to say that if you introduce any non-native species to an area, the non-native species will quickly result in the elimination of native species and the non-native becomes dominant.”

Yes, think about chili peppers and tomatoes which are new world species. Thanks to the Spanish and Portuguese these now grow around the globe. I am not aware that these plants have eliminated native species in the new world.

Then I realized something. There were quite likely hundreds of species artificially introduced to the Hawaiian islands. Most of them couldn’t actually compete with the native species and they died out quickly. Only a bare handful could actually hack it.

Technically, the Galapagos Penguins fall into this category and are endangered for specifically this/these reasons. They’re an arctic bird (arguably only being speciated geographically) and they expend lots of energy and/or sacrifice lots of real estate on an island because they have to keep their eggs cool and/or out of direct sunlight. A (not-so-)curious choice for Ron’s defense of fragile ecosystem(s).

Oh, they own far more than that:
“In 2013, there were about 198 million malaria cases (with an uncertainty range of 124 million to 283 million) and an estimated 584 000 malaria deaths (with an uncertainty range of 367 000 to 755 000).”http://www.who.int/features/factfiles/malaria/en/

RE: Population Doomster Paul Ehrlich’s New Forecast: ‘Biological Annihilation’
New predictions of animal population doom are likely exaggerated.

Oh Christ!
Not this shit again!
Assholes like Ehrlich have been preaching doom and gloom for decades with little if any correct predictions.
Gee, i wonder if these “scientists” will ask for more grant money from the taxpayer to “research” their hypothesis.

One would think Paul Ehrlich would be ashamed to show his face, much less show his face and publish anything remotely scientific.
These are the kind of people that create so much chatter and noise, most can’t hear the important stuff. Bad science and poorly done science are the cause of much of the world’s angst. It’s ridiculous these people get as much exposure as they do.

The crisis supposedly results from “the fiction that perpetual growth can occur on a finite planet”; meanwhile, “the window for effective action is very short, probably two or three decades at most.”

Thanks, Paul Erlich, but you shot yourself in the intellectual foot (where your logic lives?) with the assumption that any growth can be ‘perpetual’.

Extrapolating linear or even exponential growth “to infinity” is a fool’s errand and is basically designed to get attention.
Paul, your catastrophizing is common today all over the place, but you just make yourself look like a gadfly looking for more income from book sales when you “forecast” shit like that.

You may enjoy success from such proclamations, but you surely won’t get universal admiration for the way you’re doing it.